source: rtems/bsps/powerpc/tqm8xx/start/bspstart.c @ 511dc4b

5
Last change on this file since 511dc4b was 511dc4b, checked in by Sebastian Huber <sebastian.huber@…>, on 06/19/18 at 07:09:51

Rework initialization and interrupt stack support

Statically initialize the interrupt stack area
(_Configuration_Interrupt_stack_area_begin,
_Configuration_Interrupt_stack_area_end, and
_Configuration_Interrupt_stack_size) via <rtems/confdefs.h>. Place the
interrupt stack area in a special section ".rtemsstack.interrupt". Let
BSPs define the optimal placement of this section in their linker
command files (e.g. in a fast on-chip memory).

This change makes makes the CPU_HAS_SOFTWARE_INTERRUPT_STACK and
CPU_HAS_HARDWARE_INTERRUPT_STACK CPU port defines superfluous, since the
low level initialization code has all information available via global
symbols.

This change makes the CPU_ALLOCATE_INTERRUPT_STACK CPU port define
superfluous, since the interrupt stacks are allocated by confdefs.h for
all architectures. There is no need for BSP-specific linker command
file magic (except the section placement), see previous ARM linker
command file as a bad example.

Remove _CPU_Install_interrupt_stack(). Initialize the hardware
interrupt stack in _CPU_Initialize() if necessary (e.g.
m68k_install_interrupt_stack()).

The optional _CPU_Interrupt_stack_setup() is still useful to customize
the registration of the interrupt stack area in the per-CPU information.

The initialization stack can reuse the interrupt stack, since

  • interrupts are disabled during the sequential system initialization, and
  • the boot_card() function does not return.

This stack resuse saves memory.

Changes per architecture:

arm:

  • Mostly replace the linker symbol based configuration of stacks with the standard <rtems/confdefs.h> configuration via CONFIGURE_INTERRUPT_STACK_SIZE. The size of the FIQ, ABT and UND mode stack is still defined via linker symbols. These modes are rarely used in applications and the default values provided by the BSP should be sufficient in most cases.
  • Remove the bsp_processor_count linker symbol hack used for the SMP support. This is possible since the interrupt stack area is now allocated by the linker and not allocated from the heap. This makes some configure.ac stuff obsolete. Remove the now superfluous BSP variants altcycv_devkit_smp and realview_pbx_a9_qemu_smp.

bfin:

  • Remove unused magic linker command file allocation of initialization stack. Maybe a previous linker command file copy and paste problem? In the start.S the initialization stack is set to a hard coded value.

lm32, m32c, mips, nios2, riscv, sh, v850:

  • Remove magic linker command file allocation of initialization stack. Reuse interrupt stack for initialization stack.

m68k:

  • Remove magic linker command file allocation of initialization stack. Reuse interrupt stack for initialization stack.

powerpc:

  • Remove magic linker command file allocation of initialization stack. Reuse interrupt stack for initialization stack.
  • Used dedicated memory region (REGION_RTEMSSTACK) for the interrupt stack on BSPs using the shared linkcmds.base (replacement for REGION_RWEXTRA).

sparc:

  • Remove the hard coded initialization stack. Use the interrupt stack for the initialization stack on the boot processor. This saves 16KiB of RAM.

Update #3459.

  • Property mode set to 100644
File size: 3.4 KB
Line 
1/**
2 * @file
3 *
4 * @ingroup tqm8xx
5 *
6 * @brief Source for BSP startup code.
7 */
8
9/*
10 * Copyright (c) 2008
11 * Embedded Brains GmbH
12 * Obere Lagerstr. 30
13 * D-82178 Puchheim
14 * Germany
15 * rtems@embedded-brains.de
16 *
17 * The license and distribution terms for this file may be
18 * found in the file LICENSE in this distribution or at
19 * http://www.rtems.org/license/LICENSE.
20 */
21
22#include <stdlib.h>
23
24#include <rtems.h>
25#include <rtems/counter.h>
26
27#include <libcpu/powerpc-utility.h>
28
29#include <bsp.h>
30#include <bsp/vectors.h>
31#include <bsp/bootcard.h>
32#include <bsp/irq-generic.h>
33
34#ifdef BSP_HAS_TQMMON
35/*
36 * FIXME: TQ Monitor structure
37 */
38#endif /* BSP_HAS_TQMMON */
39
40/* Configuration parameters for console driver, ... */
41uint32_t BSP_bus_frequency;
42
43/* Configuration parameter for clock driver */
44uint32_t bsp_time_base_frequency;
45
46/* Legacy */
47uint32_t bsp_clicks_per_usec; /* for PIT driver: OSCCLK */
48
49static const char *bsp_tqm_get_cib_string( const char *cib_id)
50{
51  char srch_pattern[10] = "";
52  char *fnd_str;
53  /*
54   * create search pattern
55   */
56  strcat(srch_pattern,"-");
57  strncat(srch_pattern,
58          cib_id,
59          sizeof(srch_pattern)-1-strlen(srch_pattern));
60  strncat(srch_pattern,
61          " ",
62          sizeof(srch_pattern)-1-strlen(srch_pattern));
63  /*
64   * search for pattern in info block (CIB)
65   */
66  fnd_str = strstr((const char *)TQM_CONF_INFO_BLOCK_ADDR,srch_pattern);
67
68  if (fnd_str == NULL) {
69    return NULL;
70  }
71  else {
72    /*
73     * found? then advance behind search pattern
74     */
75    return fnd_str + strlen(srch_pattern);
76  }
77}
78
79static rtems_status_code  bsp_tqm_get_cib_uint32( const char *cib_id,
80                                           uint32_t   *result)
81{
82  const char *item_ptr;
83  char *end_ptr;
84  item_ptr = bsp_tqm_get_cib_string(cib_id);
85  if (item_ptr == NULL) {
86    return RTEMS_INVALID_ID;
87  }
88  /*
89   * convert string to uint32
90   */
91  *result = strtoul(item_ptr,&end_ptr,10);
92  return RTEMS_SUCCESSFUL;
93}
94
95uint32_t _CPU_Counter_frequency(void)
96{
97  return bsp_time_base_frequency;
98}
99
100void bsp_start( void)
101{
102  /*
103   * Get CPU identification dynamically. Note that the get_ppc_cpu_type()
104   * function stores the result in global variables so that it can be used
105   * later...
106   */
107  get_ppc_cpu_type();
108  get_ppc_cpu_revision();
109
110  /* Basic CPU initialization */
111  cpu_init();
112
113  /*
114   * Enable instruction and data caches. Do not force writethrough mode.
115   */
116
117#if BSP_INSTRUCTION_CACHE_ENABLED
118  rtems_cache_enable_instruction();
119#endif
120
121#if BSP_DATA_CACHE_ENABLED
122  rtems_cache_enable_data();
123#endif
124
125  /*
126   * This is evaluated during runtime, so it should be ok to set it
127   * before we initialize the drivers.
128   */
129
130  /* Initialize some device driver parameters */
131  /*
132   * get the (internal) bus frequency
133   * NOTE: the external bus may be clocked at a lower speed
134   * but this does not concern the internal units like PIT,
135   * DEC, baudrate generator etc)
136   */
137  if (RTEMS_SUCCESSFUL !=
138      bsp_tqm_get_cib_uint32("cu",
139                             &BSP_bus_frequency)) {
140    rtems_panic("Cannot determine BUS frequency\n");
141  }
142
143  bsp_time_base_frequency = BSP_bus_frequency / 16;
144  bsp_clicks_per_usec = bsp_time_base_frequency / 1000000;
145
146  /* Initialize exception handler */
147  ppc_exc_initialize(
148    (uintptr_t) _Configuration_Interrupt_stack_area_begin,
149    rtems_configuration_get_interrupt_stack_size()
150  );
151
152  /* Initalize interrupt support */
153  bsp_interrupt_initialize();
154
155#ifdef SHOW_MORE_INIT_SETTINGS
156  printk("Exit from bspstart\n");
157#endif
158}
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